<script setup lang="ts">
import { RouterLink, RouterView } from 'vue-router'
import HelloWorld from './components/HelloWorld.vue'

import { onMounted, computed, ref } from 'vue';
onMounted(() => {
  function simulateLongTask(duration: number) {
    const start = performance.now();
    while (performance.now() - start < duration) {
      // 空循环体
    }
  }

  // 模拟一个持续 2 秒的长任务
  // simulateLongTask(500);
})

const opacity = ref('visible')
const color = ref('red')
const computedStyle = computed(() => {
  return {
    opacity: opacity.value,
    'background-color': color.value,
    'visibility': opacity.value
  }
})
</script>

<template>
  <header>
    <!-- <img alt="Vue logo" class="logo" src="@/assets/logo.svg" width="125" height="125" /> -->
    <picture>
      <!-- 优先使用 AVIF 格式 -->
      <source type="image/avif" media="(max-width: 320px)"
        srcset="@/assets/bk_320x240.avif 1x @/assets/bk_640x480.avif 2x">
      <source type="image/avif" media="(max-width: 640px)"
        srcset="@/assets/bk_640x480.avif 1x @/assets/bk_1024x768.avif 2x">
      <source type="image/avif" media="(max-width: 10240px)"
        srcset="@/assets/bk_1024x768.avif 1x @/assets/bk_1024x768.avif 2x">

      <!-- 其次使用 WebP 格式 -->
      <source type="image/webp" media="(max-width: 320px)"
        srcset="@/assets/bk_320x240.webp 1x @/assets/bk_640x480.webp 2x">
      <source type="image/webp" media="(max-width: 640px)"
        srcset="@/assets/bk_640x480.webp 1x @/assets/bk_1024x768.webp 2x">
      <source type="image/webp" media="(max-width: 10240px)"
        srcset="@/assets/bk_1024x768.webp 1x @/assets/bk_1024x768.webp 2x">

      <!-- 最后使用 PNG 格式 -->
      <source type="image/png" media="(max-width: 320px)"
        srcset="@/assets/bk_320x240.png 1x @/assets/bk_640x480.png 2x">
      <source type="image/png" media="(max-width: 640px)"
        srcset="@/assets/bk_640x480.png 1x @/assets/bk_1024x768.png 2x">
      <source type="image/png" media="(max-width: 10240px)"
        srcset="@/assets/bk_1024x768.png 1x @/assets/bk_1024x768.png 2x">

      <!-- 默认图像资源（PNG 格式） -->
      <img src="@/assets/bk.png" alt="Elva dressed as a fairy">
    </picture>

    <div class="wrapper">
      <HelloWorld msg="You did it!" />
      <nav>
        <RouterLink to="/">Home</RouterLink>
        <RouterLink to="/about">About</RouterLink>
      </nav>
    </div>
  </header>

  <RouterView />
</template>

<style scoped>
header {
  line-height: 1.5;
  max-height: 100vh;
}

.logo {
  display: block;
  margin: 0 auto 2rem;
}

nav {
  width: 100%;
  font-size: 12px;
  text-align: center;
  margin-top: 2rem;
}

nav a.router-link-exact-active {
  color: var(--color-text);
}

nav a.router-link-exact-active:hover {
  background-color: transparent;
}

nav a {
  display: inline-block;
  padding: 0 1rem;
  border-left: 1px solid var(--color-border);
}

nav a:first-of-type {
  border: 0;
}

@media (min-width: 1024px) {
  header {
    display: flex;
    place-items: center;
    padding-right: calc(var(--section-gap) / 2);
  }

  .logo {
    margin: 0 2rem 0 0;
  }

  header .wrapper {
    display: flex;
    place-items: flex-start;
    flex-wrap: wrap;
  }

  nav {
    text-align: left;
    margin-left: -1rem;
    font-size: 1rem;

    padding: 1rem 0;
    margin-top: 1rem;
  }
}

iframe {
  border: none;
}
</style>
